G agents: Prophage elements conferring high mutability of host neighbouring gene tonB, high spontaneous production of particles and cell elongation

Summary A certain form of hybridization between two prophages leads to the formation of abnormal lysogens characterized by a high rate of deletions covering the membrane gene tonB close to the prophage, a high spontaneous production of particles and morphological changes such as elongation of the host cell. As bacteria are remarkable by their inalterable shape, the control of phage production and the low rate of mutations, these observations indicate an alteration of a basic mechanism in bacterial cell regulation induced by a certain form of hybrid prophage, still undetermined and named here G agents.